====== Alphanumeric LCD ======

//Related to: [HW] [[en:hardware:homelab:digi]]//

This library contains functions to use the HomeLab alphanumeric LCD.

===== Data Types =====

  * **//lcd_alpha_mode//** \\ LCD configuration enumeration data type. Options:
    * //LCD_ALPHA_DISP_OFF// - Display off.
    * //LCD_ALPHA_DISP_ON// - Display on with invisible cursor.
    * //LCD_ALPHA_DISP_ON_CURSOR// - Display on with cursor.
    * //LCD_ALPHA_DISP_ON_CURSOR_BLINK// - Display on with blinking cursor.

===== Functions =====

  * **//void lcd_alpha_init(lcd_alpha_mode disp_attr)//** \\
    Initializes LCD. Parameters:
    * //disp_attr// - Display configuration.

  * **//void lcd_alpha_clear(void)//** \\
    Clears the whole display. Cursor is moved to the beginning of the first line.

  * **//void lcd_alpha_clear_line(unsigned char line)//** \\
    Clears a line on display. Cursor is moved to the beginning of cleared line. Parameters:
    * //line// - Line number. 0 or 1.

  * **//void lcd_alpha_home(void)//** \\
    Moves cursor to the beginning of the first line.

  * **//void lcd_alpha_goto_xy(unsigned char x, unsigned char y)//** \\
    Moves cursor to the desired position. Parameters.
    * //x// - X coordinate (column number). 0 to 15.
    * //y// - Y coordinate (line number). 0 to 1.

  * **//void lcd_alpha_write_char(char c)//** \\
    Writes a character to the cursor position. Parameters:
    * //c// - ASCII character.

  * **//void lcd_alpha_write_string(const char *s)//** \\
    Writes a string to the display starting from the position of the cursor. Parameters:
    * //s// - Pointer to string (char array).

  * **//void lcd_alpha_write_string_p(const char *progmem_s)//** \\
    Writes a string from program memory to the display starting from the position of the cursor. Parameters
    * //progmem_s// - Pointer to string in program memory.

===== Example =====

Demonstration of how to use alphanumeric LCD to display text.

<code c>
#include <homelab/module/lcd_alpha.h>

int main(void)
{
	// LCD initialization.
	lcd_alpha_init(LCD_ALPHA_DISP_ON);

	// Display clearing.
	lcd_alpha_clear();

	// Cursor to the beginning of second line.
	lcd_alpha_goto_xy(0, 1);	

	// Text displaying.
	lcd_alpha_write_string("Hello");
}
</code>